Q10 of 136 Page 28

If a line makes angle with x-axis and y-axis respectively, then the angle made by the line with z-axis is

If a line makes angles α , β and γ with the axes then,


cos2α + cos2β + cos2γ = 1 → (1)


Here,


α


β


Now,


cos2α + cos2β + cos2γ = 1


cos2 + cos2 + cos2γ = 1


+ + cos2γ = 1


+ cos2γ = 1


cos2γ = 1 -


cos2γ


cosγ


γ

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